The extensive use of chemical pesticides poses risks to the environment and human health due to the toxicity and poor biodegradability.
Alternative natural practices, including the use of natural molecules, are needed to achieve more sustainable
production methods to meet consumer and societal expectations. Plants contain a wide range of potential phytochemicals
that target a specific target, are rapidly biodegradable, are environmentally friendly, and have a variety of therapeutic effects,
making them a treasure trove of biological materials.
Methods Toxicity of hot Capsicum annuum extracts was tested against 3rd
instar larvae of Culex pipiens and Musca domestica.
LC₅₀ values were determined using serial concentrations, and phytochemical profiling was performed to identify active
compounds with molecular docking studies.
Results In this study, different exposure periods of various Capsicum annuum extracts showed high insecticidal activity
against mosquito and housefly larvae. The petroleum ether (CAPe) extract from C. annuum was the most effective (100
MO%) against Culex pipiens (
LC50 = 150.46 ppm) and Musca domestica larvae (
LC50 = 0.18 mg/ml) 24 h after treatment.
The LC50
dose of the CAPe extract led to a negative effect on the insect metabolism process represented by a significant
decrease in the activity level of protease, lipase, α-amylase, and invertase enzymes in both mosquito and fly larvae. Antimicrobial
activity tests showed that the CAPe extract killed all of the microbes that were tested, except for Penicillium
glabrum. The UPLC/MS comparison of the four Capsicum extracts led to the possible identification of eighty metabolites.
The large amounts of flavonoids, phenolic acids, and capsaicinoids were in line with what has been written about the genus
Capsicum. Moreover, the multivariate data analysis showed that capsaicinoids, sophorolipids, triterpenoids, and phenolic
acids were abundant in the methanol extract compared to flavonoids, triterpenoids, and fatty acids for the petroleum ether
extract. Simultaneously, the docking results showed that all of the docked compounds could fit into the digestive lysosome
active site of M. domestica (2H5Z).
Conclusions The major compounds in petroleum ether extract were able to interact with essential amino acids at the target
sites of both Cx. pipiens and M. domestica, and therefore the insects’ life-supporting functions were negatively affected.
Overall, CAPe extract from Capsicum annuum could be a promising ecofriendly bioinsecticide. |
